There are many types of medical electrodes known in the industry.
One of such electrodes is described in U.S. Pat. No. 3,150,430. A typical medical electrode usually consists of a core with a rigid sharp end and a socket with a central aperture. Six electrode apertures are situated at the perimeter thereof and have center lines which are parallel to a center line of the central aperture. A cage of the electrode is an additional component of the socket formed by six elements welded to hold an apex.
A technical drawback of this electrode is that it is not interchangeable and can be used only once.
Another electrode is described in German Patent 3316837. This electrode consists of a cage formed by three elements that support a mandrel. An apex is placed in a cylindrical shaped bar and is changeable and adjustable. A core which ends in the mandrel holds the apex.
The mass of the mandrel causes increase in kinetic moment which results in the increase of the stresses in the elements supporting the mandrel. This decreases the life span and reliability of the electrode. Manufacturing of such electrodes is complex and their use leads to a significant loss of energy.